Conventionally, a flat and thin display device that is used for an electronic appliance includes at least a display panel that displays an image and a backlight device that delivers light from a rear surface of the display panel. This type of display device often employs a double-sided tape with stickiness in bonding components together. For example, the display panel may be fixed to a frame of the backlight device with the double-sided tape. To the double-sided tape, static and dynamic force is applied constantly. An example of such a system is disclosed in Japanese Patent Application Publication No. 2013-238888.
The holding power by the double-sided tape tends to decrease over time due to, for example, a difference in thermal expansion rate with respect to a temperature change between the display panel and the frame. If the partial separation should occur due to such a decrease in holding power, the stress applied to the display panel becomes inhomogeneous and display unevenness may occur. In addition, as the holding power decreases, the display panel may deviate from a predetermined position of the frame or be detached due to its own weight and accordingly, the reliability of the display device decreases. Such a decrease in holding power is observed particularly on the display panel side, where the flatness is higher than on the frame side.
Moreover, in recent years, the narrower-frame models have been developed. In such a structure, it is difficult to sufficiently secure the area to paste the double-sided tape and thus, it is necessary to secure the sufficient holding power in the narrow area.